`licenses` metadata in package.json is invalid

[zachleat]

https://docs.npmjs.com/cli/v10/configuring-npm/package-json?v=true#license

// Not valid metadata
{
  "licenses" : [
    {
      "type": "MIT",
      "url": "https://www.opensource.org/licenses/mit-license.php"
    },
    {
      "type": "Apache-2.0",
      "url": "https://opensource.org/licenses/apache2.0.php"
    }
  ]
}

Needs to be a single license property instead.